([1]})
Let the linear system \(A=\) , with the coefficient matrix \(A \in ^{m\times n}\)  and the right-hand side \(\in ^{m}\) , be consistent. Then the iteration sequence \(\left\lbrace ^{(k )}\right\rbrace _{k=0}^{\infty }\) , generated by the RGRK method starting from an initial guess in the column space of \(A^T\) , converges to the unique least norm solution \(^{\ast }=A^{\dag }\)  in expectation. Moreover, for \(k\ge 1\) , the solution error in expectation for the iteration sequence \(\left\lbrace ^{(k )}\right\rbrace _{k=0}^{\infty }\)  obeys
\( {^{(k+1)} - A^\dag }\le \left(1 - \tau \frac{\sigma _{\min }^2(A)}{{A}} \right){^{(k)} - A^\dag },\) 
